public class Example {
    String str = new String("hello");
    char[] ch = {'a','b'};

    public static void main(String[] args) {
        Example ex = new Example();
        ex.change(ex.str,ex.ch);
        System.out.print(ex.str+"and");
        System.out.print(ex.ch);
    }
    public void change(String str,char ch[]){
        str = "test ok";
        ch[0] ='c';
    }
}
